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Ex Vivo Assessment of Contractility, Fatigability and Alternans in Isolated Skeletal Muscles
Published on: November 1, 2012
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Skeletal Muscle Fatigability in Heart Failure.
Manda L Keller-Ross1, Mia Larson1, Bruce D Johnson2
1Divisions of Physical Therapy and Rehabilitation Science, Department of Rehabilitation Medicine, Medical School, University of Minnesota, Minneapolis, MN, United States.
Frontiers in Physiology
|March 9, 2019
Summary
Heart failure patients exhibit skeletal muscle fatigability, leading to exercise intolerance. Understanding muscle fatigability mechanisms is crucial for developing effective rehabilitative strategies to improve functional capacity.
Area of Science:
- Cardiology
- Exercise Physiology
- Skeletal Muscle Physiology
Background:
- Heart failure (HF) patients commonly experience skeletal muscle fatigability, particularly in lower limbs during exertion.
- The precise contribution of skeletal muscle fatigability to exercise intolerance symptoms like perceived fatigue and dyspnea in HF remains incompletely understood.
Purpose of the Study:
- This review aims to elucidate skeletal muscle fatigability in HF patients.
- It will explore the underlying mechanisms driving locomotor skeletal muscle fatigability in HF.
- The review will also examine the relationship between muscle fatigability and perceived fatigue/exercise intolerance symptoms in HF.
Main Methods:
- This is a review article, synthesizing existing evidence on skeletal muscle fatigability in heart failure.
- It discusses objective measures of muscle fatigability (reduced force/power) versus subjective perceived fatigue.
- The review examines mechanisms contributing to locomotor muscle fatigability.
Main Results:
- Evidence indicates HF patients exhibit greater skeletal muscle fatigability compared to healthy individuals.
- This fatigability may significantly impair motor performance and contribute to exercise intolerance.
- Cardiac dysfunction alone is insufficient to explain exercise intolerance in HF.
Conclusions:
- Skeletal muscle fatigability is a key factor in exercise intolerance among heart failure patients.
- Understanding these muscle-specific mechanisms is vital for designing targeted rehabilitation strategies.
- Improving motor performance and functional capacity in HF necessitates addressing skeletal muscle issues.
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